The learning benefits of CLIL in secondary education contexts have been documented in many studies across Europe, including Catalonia. However, research confirms that the attention paid to language in CLIL programs is often insufficient, and full and proper integration of content and language is actually rare. In Sant Llorenç de Morunys high school, students of 1st year of ESO do Social Science in English, in a two-hour weekly lesson focused on Collaborative Language Learning (CLL). During my practicum observation period, I detected a problem in this class: language structures were not given the same weight as the content, so a focus on form was practically absent. This paper seeks to provide an innovation proposal which replaces this teaching approach by working with focus-on-form CLIL in the Social Science class. The unit created has a focus on form in order to potentiate the acquisition of certain content-related structures apart from the content of the unit itself. In other words, my proposal is focused on creating language learning opportunities in order to favour deep content learning.